Metallic finish laminated sheet material and process of making same



Feb. 22, 1955 A. w. BATEMAN METALLIC FINISH LAMINATED SHEET MATERIAL AND PROCESS OF MAKING SAME Flled Aprll 6, 1954 INVENTOR ALvA WAYNE BATEMAN m0 IhwzmxmDODZ-...ZCU

440m Da Oo Zwama I 1.0m IPOOEW DMF/MI m0 IFwZmJ mDODZTrZOO AGENT United States Patent O METALLIC FINISH LAMINATED SHEET MATE- RlAL AND PROCESS F MAKING SAME Alva Wayne Bateman, Newburgh, N. Y., signor-to E. l. du Pont de Nemours and Company, Wilmington, Del.. ii corporation ol Delaware Application Aprll 6, 1954, Serial No. 421,387 Claims. (Cl. 154-37) This invention relates to metallic finish laminated materials and more particularly to metallic finish polyvinyl chloride sheet materials with a surface layer of polymeric linear terephthalate ester.

Coated fabrics, unsupported plastic films, coated leathers and similar sheet materials with metallic finishes lare well known to the art and have been widely used in the shoe, millinery and novelty trade because of their ornamental appearance. These metallic finishes have been produced by a variety of processes.

One such process involves applying to the surface of the sheet material to be decorated a surface layer of :i film-forming composition containing metallic pigment particles. Another process involves applying to the surface of a coated fabric a suitable adhesive, drying the adhesive until it reaches the dust-free stage, dusting on the to orient the particles so that their light reflecting faces are in one plane and finally baking to set the adhesive :ind hold the particles in the oriented position.

Other processes involve the lamination of thin metal foils to the surface of the flexible sheet materials with a suitable adhesive. Still other processes involve coating metals by vacuum distillation, cathode sputtering and flame coating directly on the surface to be metallized.

These methods result in metallic finishes of various degrees of brightness. The metallic finishes produced by these prior art methods are all subject to damage by abrasion.

lt is an object. of this invention to provide laminated structures involving a metallic finish on a flexible substrate that is not subject to damage by abrasion. A further object is the provision of a process for uniting a metallized film of polyethylene terephthalate to a tiexible substrate by means of an adhesive composition. A more specific object is the provision of a non-dulling highly heat reecting window shade material.

These and other important objects of this invention are attained by adhering the metallized side of a metallized film of polymeric linear terephthalate to a vinyl chloride polymer containing material by means of an adhesive composition comprising a polymeric alkyl acrylate or Jpolymeric alkyl methacrylate, in which the alkyl group eontains l to 8 carbon atoms, and a vinyl resin composed `of vinyl chloride, vinyl acetate and maleic or similar alpha beta olefnic unsaturated carboxylic acid.

Throughout the specification and appended claims the term polymeric terephthalate ester refers to a polymeric linear terephthalate ester of terephthalic acid and a glycol of the series HO(CH2)1OH, where n is a whole number withinthe range of 2 to l0, such as disclosed in U. S. Patent 2,465,319.

The single figure in the drawing is a diagrammatic side view of an apparatus suitable for carrying out the laminating step in accordance with this invention.

The following specific examples illustrate certain specific embodiments of the invention which are given as illustrations and not limitations. Throughout the specification and claims the percentage and parts figures are expressed on a weight basis.

EXAMPLE I A non-dulling and highly refiective mirror surface was produced on a polyvinyl chloride coated fabric base material in accordance with the following procedure:

A cotton sheeting fabric running 2.40 yards per pound adhesive fiat plate-like metal particles, burnishing 2,702,580 Patented Feb. 22, 1955 ICC . 2 per 60 inch width, thread count 56 x 60, was diastased, washed and dyed black. The fabric was doctor knife coated on one side with l coat of the following eompogi. tion:

Base coating composition Per cent by weigh Polyvinyl chloride 12.0 Dioctyl phthalate...... 8.0 Methyl ethyl ketone 80.0

Per cent by weight Polyvinyl chloride 48.0

Dioctyl phthalate 32.0 Bone black 10.0 Barytes 10.0

The plastisol composition is prepared by grinding the pigment and filler in the dioctyl phthalate, then stirring polyvinyl chloride powder in the pigment/plasticizer mixture at room temperature so as not to colloid the polyvinyl chloride. Sufficient of the plastisol composition is applied to deposit a coating of about 12.0 ounces per square yard. The coated fabric is next passed through a heat zone to heat the plastisol coating up to 3D0-375 F. at which temperature the polyvinyl chloride is colloided in the dioctyl phthalate and upon cooling a strong tough film results.

The thus described coated fabric was top coated with the following adhesive composition:

The vinyl resin (Vinylite VMCH) in the above formula was a tripolymer, the approximate composition of which may vary within the following limits:

Parts by weigh Vinyl chloride 80.090.0 Vinyl acetate 19.7-7.0

Maleic or similar alpha beta olefinic unsaturated carboxylic acid .3-3.0

The Vinylite VMCH resin may be produced in accordance with the teaching set forth in U. S. Patent 2,329,456, issued September 14, 1943, to William E. Campbell, Jr., and the limitations set forth in the disclosure of that patent apply here.

Sufficient of the above adhesive composition was applied to the polyvinyl chloride sheet material to deposit approximately .5 ounce of dry adhesive per square yard. The methyl ethyl ketone was evaporated by passing the material through a heat zone. Immediately after drying the adhesive coat and while it was at an elevated temperature and tacky, it was brought in contact with the metallized side of a .25 mil film of polyethylene terephthalate by means of pressure rolls. Alternately after the top coat is applied and dried the coated fabric may be stored and the top coat reheated immediately prior to laminating it to the metallized side of the polyethylene terephthalate film by means of an apparatus as illustrated in the drawing.

The polyethylene terephthalate film may be metallized by means of vacuum distillation of aluminum and certain aluminum alloys as described in one or more of the 3 following U. S. Patents: 2,664,852; 2,o65,223; 2,665,224; 2,665,225; 2,665,226', 2,665,227; 2,665,223; and 2,665,229.

The metallized side of the polyethylene terephthalatc film was firmly attached to the polyvinyl chloride coating and withstood about 300 mechanical scrubs before there was any separation of the metallized film from the hase material. The mechanical scrub test was carried out on an apparatus illustrated in Automotive Industries, 49, 1262-6. The mechanical scrub test simulates the condition of taking a strip of material about 6 inches long and two inches wide and firmly grasping each end between the thumbs and forefingers of each hand. making a slight S fold between each hand, and vigorously rubbing the material back and forth upon itself while under pressure. ,h

The product had a highly lustrous metallic finish that was scuff resistant and particularly adapted for fabrica tion into ladies handbags and evening slippers.

Polyvinyl chloride unsupported films may be substittuted for the polyvinyl chloride coated fabric in the above example as the base material to which the metal-1 lized iilm is laminated by means of the same adhesive composition and in like marmer. The woven cotton fabric may be replaced with knitted fabrics as well as non-woven fabrics such as those disclosed in copending application S. N. 267.9ll` led January 23, 1952, now abandoned. The fabric substrate for the polyvinyl chloride coating may be formed from a variety of synthetic fibers such as, e. g., polyethylene terephthalate, polyacrylonitrile, nylon, glass, etc., in either woven, non-- woven or knitted form.

EXAMPLE II A window shade material highly heat reflecting on one side was made by coating a cotton sheeting running 4.73 yards per pound per 38%" width, thread count 72 x 72, with one coat of the following composition on each side:

Parts by weight Vinyl resin (copolymer of 85 parts of' vinyl chlol 5 ride and parts of vinyl acetate) Phthalic diester of ethylene glycol 1.9 Triphenyl phosphate 1.9 Pigments 18.2 Methyl ethyl ketone 58.5

The coated fabric was passed through a heat zone to expel the volatile solvent and then through pressure rolls to smooth and consolidate the coating and fabric. Sui cient composition was applied to deposit about .8 ounce of dry coating per square yard on each side.

The coated fabric was given an additional coat on i each side of the following composition:

Sutiicient of the above composition was applied to deposit an additional 0.4 ounce ot' dry coating per square yard on cach side.

One side of the coated fabric was given further coating with one coat of the following adhesive composition:

I Parts by weight Vinyl resin Vinylite VMCH (same as Example 1) 22.5 Polymethyl methacryalte 7.5 Di (ethyl hexyl) phthalate 13.0 Methyl ethyl ketone 57.0

Sufhcicnt of the above adhesive composition was applied to the one side of the coated fabric to deposit about 0.5 ounce of dry coating per square yard. l. After drying the coated fabric was rolled up and stored at this stage.

Subsequently a .25 mil polyethylene terephtbalatc tilrn,

metailized on one side (same as in Example l), was laminated to the side of the coated fabric with the afi hesive coat by means of an apparatus illustrated in thc drawing, with the metallizcd side of the polyethylene terephthalatefilm contiguous with thc adhesive layer. The adhesive or bonding coat was activated just prior to being brought in pressure contact with the metallized side of the polyethylene terephthalate film by passing under a source of radiant heat.

T he adhesive composition of this invention may coutain from 5% to 50% of polymeric acryiate or polymeric alkyl methaciylate, in which the alkyl group contains l to 8 carbon atoms, based on the combined weight oi thc acrylate or methacrylate and the vinyl resin.

in the interest of brevity a specific example illustrating each polymeric alkyl acrylatc or polymeric alkyl inethacrylate that may be blended with the vinyl resin in the adhesive composition is not given, however, it will be understood that the polymeric alkyl methacrylates and the polymeric alkyl acrylatcs, in which the alkyl group contains l to carbon atoms. may be substituted on a pound for pound basis for the polymethyl methacrylate used in the specific examples of the adhesive composition.

in place ot polyvinyl chloride in the flexible base material it will be readily apparent that copolymers ot vinyl chloride and other materials copolymerizablc therewith such as vinyl acetate, lower alkyl fumarates such as methyl and ethyl fumarates, acrylic and methacrylic esters, and vinylidene chloride are useful materialsin preparing the base materials to which the metallized side of metallized polyethylene terephthalate film may be adhered. ln the claims the term vinyl chloride polymer is used to denote both homopolymers and copolymers.

Polyvinyl chloride coated leather may also bc used as the base material to which the metallized polyethylene terephthalate film is laminated with the adhesive compo sition described above.

in place of the linear polyethylene terephthalatc used in the specific examples the highly polymerized esters obtained by the reaction of terephthalic acid and polymethylene glycols having more than two but not more than l0 methylene groups may also be used in this invention; such as, e. g., trirnethylene glycol, tetramcthylene glycol, hexamethylene glycol, heptamethylene glycol. octamethylene glycol, nonamethylene glycol and decamethylene glycol. The glycols having 2 to 4 methylene groups are preferred.

There is no particular limit to be placed on the thickv ness of the polymeric terephthalate ester surface tilm For economic advantages it is desirable to use as thin i: iilm as possible and .25 mil thick films have been found well suited for the products of this invention. Wheri flexibility is not important much thicker polymeric ter elphhalate ester films may be used, such as, e. g. 4 to 5 mils t ic Colored metallic finishes may be made by applying a suitably colored translucent composition as an ultimate surface coat to laminated assembly described above. For the colored composition a solution of polyethylene terephtlialatc in highly polar solvents auch as formamide. nitrobenzene, phenol and meta cresci, at relatively high temperatures, containing spirit soluble dyes may be used.

Unusual surface effects may be realized by using an engraved steel roller in place oE the smooth surface roller for the laminating step. The laminated products of this invention may also be embossed by conventional cmy'bossing equipment such as roller or plate embossing ap paratus.

The products ot this invention may be laminated to bulky non-woven webs, such as, e. g., those described in copending applications S. N. 267,911. now abandoned and S. N. 267,912, filed January 23, 1952, by E. A. Rod man. ln this feature of the invention the sid-e of tht yflexible base material opposite the metallic finish is cc mented -to the bulky nondwoven webs by means of suitable adhesives, such as, e. g., a solution of polyvinyl chloride resin or copolymer of vinyl chloride and vinyl acetate in a ketone solvent, such as, e. g., methyl ethyl ketone.

The products of? this invention combine the advantages of the high luster Aof a polished metallic surface with the flexibility and the other advantageous properties of th'.

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flexible backing materials. The products of this invention are greatly su rior to the combination of metal foil combined to fiexi le base materials in that the finished p roduct can be subjected to repeated scrubbing as described above, without disturbing the metallic finish. They are also more supple than the metal foil laminated products. The products of this invention are extremely scufi resistant. The metallic finish is also protected from oxidation or other corrosive conditions by the layer of polyethylene terephthalate. The polyethylene terephthalate surface is also extremely solvent resistant to most common organic solvents.

Thus in various physical characteristics the products of the presentinvention have distinctively desired characteristics of practical value not possessed by prior are metallized finishes on flexible back materials.

lt is apparent that many widely different embodiments of this invention may be made without departing from the spirit and scope thereof and, therefore, it is not intended to be limited except as indicated in the appended claims.

I claim: l. A highly lustrous laminated assembly comprising a flexible base material, the surface of which comprises a.

vinyl chloride polymer, an intermediate adhesive layer containing a tripolymer of from 80% to 90% vinyl chloride, from 19.7% to 7.0% of vinyl acetate and from .3% to 3.0% of an alpha beta olefinic unsaturated carboxylic acid, and an acrylic polymer selected from the group consisting of polymeric alkyl acrylates and polymeric alkyl methacrylates, said alkyl group containing l to 8 carbon atoms, said adhesive layer being contiguous with said surface, and a surface layer comprising a film of polymeric linear terephthalate metallized on one side, the metallized side of said lm being contiguous with said adhesive layer, the acrylic polymer in the adhesive layer comprising to 50% of the combined weight of the acrylic polymer and the tripolymer in the adhesive layer.

2. The product of claim 1 in which the vinyl chloride polymer in the base material is a homopolymer of vinyl chloride.

3. The product of claim l in which the acrylic polymerv in the adhesive layer is polymethyl methacrylate. 4. The product of claim 1 in which the polymeric linear terephthalate is polyethylene terephthalate.

5. The product of claim 1 in which the polymeric linear tercphthalate film is about .25 mil thick.

6. A highly reflective window shade material comprisin a fabric base coated on each side with a vinyl chloride o ymer containing composition, an intermediate adesive layer firmly attached to one side of said coated fabric, said adhesive layer comprising a tripolymer of Ifrom to 90% vinyl chloride, from 19.7% to 7.0% of vinyl acetate, and from .3% to 3.0% of an alpha bets olefinic unsaturated carboxylic acid, andan acrylic polymer selected from the class consisting of polymeric alkyl acrylates and polymeric alkyl methacrylates, said alkyl group containing 1 to 8 carbon atoms, and a surface layer of a lm of polymeric linear terephthalate metallized on one side, the metallized side of said film being firmly attached to said adhesive layer, the acrylic polymer in the adhesive layer comprising 5% to 50% of the combined weight of the acrylic polymer and the tripolymer in the adhesive layer.

7. The process which comprises coating the surface of a flexible vinyl chloride polymer containing base material with an intermediate adhesive composition, said adhesive composition com rising a volatile solvent and a tripolymer of from 80 o to 90% vinyl chloride, from 19.7% to 7.0% vinyl acetate and from .3% to 3.0% of an alpha beta olefinic unsaturated carboxylic acid, and an acrylic polymer selected from the class consisting of olymerlc alkyl acrylates and polymeric alkyl methacry ates, said alkyl group containing 1 to 8 carbon atoms, removing the volatile solvent from the adhesive composition, and ressing the metallized side of a metallized polymeric near terephthalate film against the dry adhesive composition while said adhesive is at an elevated temperature, the acrylic polymer in the adhesive composition comprising 5% to 50% of the combined weight of the acrylic polymer and tripolymer in the adhesive composition.

8. The process of claim 7 in which the vinyl chloride polymer is a homopolymer of vinyl chloride.

9. The process of claim 7 in which the polymeric linear terephthalate is polyethylene terephthalate. 10. 'I'he process of claim 7 in which the acrylic pogmer in the adhesive composition is polymethyl me acrylate.

References Cited in the le of this patent UNITED STATES PATENTS 2,039,372 Wickmann May 5. 1936 .2,310,712 Schmied Feb. 9, 1943 2,525,863 Carter Oct. 17, 1950 2,613,168 Totten Oct. 7, 1952 

1. A HIGHLY LUSTROUS LAMINATED ASSEMBLY COMPRISING A FLEXIABLE BASE MATERIAL, THE SURFACE OF WHICH COMPRISES A VINYL CHLORIDE POLYMER, AN INTERMEDIATE ADHESIVE LAYER CONTAINING A TRIPOLYMER, OF FROM 80% TO 90% VINYL CHLORIDE FROM 19.7% TO 7.0% OF VINYL ACETATE AND FROM .3% TO 3.% OF AN ALPHA BETA OLEFINIC UNSATURATED CARBOXYLIC ACID, AND AN ACRYLIC POLYMER SELECTED FROM THE GROUP CONSULTING OF POLYMERIC ALKYL ACRYATES AND POLYMERIC ALKYL METHACRYLATES, SAID ALKYL GROUP CONTAINING 1 TO 8 CARBON ATOMS, SAID ADHESIVE LAYER BEING CONTIGUOUS WITH SAID SURFACE, AND A SURFACE LAYER COMPRISING A FLIM OF POLYMERIC LINEAR TEREPHTALATE METALLIZED ON ONE SIDE THE METALLIZED SIDE OF SAID FILM BEING CONTIGUOUS WITH SAID ADHESIVE LAYER, THE ACRYLIC POLYMER IN THE ADHESIVE LAYER COMPRISING 5% TO THE COMBINED WEIGHT OF THE ACRYLIC POLYMER AND THE TRIPOYLMER IN THE ADHESIVE LAYER. 